Mere is an adjective that can mean small, unimportant, or insignificant, or that something small has a big effect or influence. Learn how to use mere in different contexts and examples with Britannica Dictionary. Mere is an adjective that means very small, unimportant, or insignificant. It is used before a noun and can be followed by the superlative form of an adjective or a noun. See examples, synonyms, and word origin. Discover the meaning of mere, what mere means, and how to use mere correctly. Complete guide with definitions, examples, and usage tips. 6 meanings: being nothing more than something specified 1. archaic or dialect a lake or marsh 2. obsolete the sea or an inlet.... Click for more definitions.